Today's SAT math question

To make an orange dye, 3 parts of red dye are mixed with 2 parts of yellow dye. To make a green dye, 2 parts of blue dye are mixed with 1 part of yellow dye. If equal amounts of green and orange are mixed, what is the proportion of yellow dye in the new mixture?

This is not a homework question btw. My answer is 3/8. Yet the correct answer is 11/30. Can anyone explain why?

To make an orange dye, 3 parts of red dye are mixed with 2 parts of yellow dye. To make a green dye, 2 parts of blue dye are mixed with 1 part of yellow dye. If equal amounts of green and orange are mixed, what is the proportion of yellow dye in the new mixture?

This is not a homework question btw. My answer is 3/8. Yet the correct answer is 11/30. Can anyone explain why?